1. 30 Jul, 2015 3 commits
    • David Howells's avatar
      PKCS#7: Appropriately require or forbid authenticated attributes · 37ce40fa
      David Howells authored
      A PKCS#7 or CMS message can have per-signature authenticated attributes
      that are digested as a lump and signed by the authorising key for that
      signature.  If such attributes exist, the content digest isn't itself
      signed, but rather it is included in a special authattr which then
      contributes to the signature.
      
      Further, we already require the master message content type to be
      pkcs7_signedData - but there's also a separate content type for the data
      itself within the SignedData object and this must be repeated inside the
      authattrs for each signer [RFC2315 9.2, RFC5652 11.1].
      
      We should really validate the authattrs if they exist or forbid them
      entirely as appropriate.  To this end:
      
       (1) Alter the PKCS#7 parser to reject any message that has more than one
           signature where at least one signature has authattrs and at least one
           that does not.
      
       (2) Validate authattrs if they are present and strongly restrict them.
           Only the following authattrs are permitted and all others are
           rejected:
      
           (a) contentType.  This is checked to be an OID that matches the
           	 content type in the SignedData object.
      
           (b) messageDigest.  This must match the crypto digest of the data.
      
           (c) signingTime.  If present, we check that this is a valid, parseable
           	 UTCTime or GeneralTime and that the date it encodes fits within
           	 the validity window of the matching X.509 cert.
      
           (d) S/MIME capabilities.  We don't check the contents.
      
           (e) Authenticode SP Opus Info.  We don't check the contents.
      
           (f) Authenticode Statement Type.  We don't check the contents.
      
           The message is rejected if (a) or (b) are missing.  If the message is
           an Authenticode type, the message is rejected if (e) is missing; if
           not Authenticode, the message is rejected if (d) - (f) are present.
      
           The S/MIME capabilities authattr (d) unfortunately has to be allowed
           to support kernels already signed by the pesign program.  This only
           affects kexec.  sign-file suppresses them (CMS_NOSMIMECAP).
      
           The message is also rejected if an authattr is given more than once or
           if it contains more than one element in its set of values.
      
       (3) Add a parameter to pkcs7_verify() to select one of three options:
      
           (A) Require pkcs7_data type content and forbid authattrs entirely.
      
           (B) Require pkcs7_data type content and require authattrs but to
           	 reject Microsoft Authenticode authattrs.
      
           (C) Require an Authenticode type content (only indirect data is
           	 currently supported) and permit/require certain Authenticode
           	 authattrs.
      
       (4) Have module verification choose option (A) above.  This means that
           with module signing, the signature is over the content digest only.
           sign-file sets CMS_NOATTR to suppress authattrs.  We could be more
           flexible and permit (A) or (B) for module signing.
      
       (5) Have kexec verification of PE executables choose option (C) above.  We
           may need to relax this if signed PE files may be encountered that
           don't have authattrs in their PKCS#7 message.
      
           Kexec does not currently verify non-PE executables - but if this is
           added in the future it should probably use option (A).
      
       (6) The pkcs7_test key type is given a module parameter to select between
           the above options for testing purposes.
      
      Future patches add firmware signing support.  Firmware signing will require
      a signed authattr containing the firmware name as passed to
      request_firmware() and so would pick option (B) above, but we would also
      need to permit the firmware name authattr.
      Suggested-by: default avatarAndy Lutomirski <luto@kernel.org>
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Reviewed-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
      37ce40fa
    • David Howells's avatar
      ASN.1: Fix actions on CHOICE elements with IMPLICIT tags · a35dc3f2
      David Howells authored
      In an ASN.1 description where there is a CHOICE construct that contains
      elements with IMPLICIT tags that refer to constructed types, actions to be
      taken on those elements should be conditional on the corresponding element
      actually being matched.  Currently, however, such actions are performed
      unconditionally in the middle of processing the CHOICE.
      
      For example, look at elements 'b' and 'e' here:
      
      	A ::= SEQUENCE {
      			CHOICE {
      			b [0] IMPLICIT B ({ do_XXXXXXXXXXXX_b }),
      			c [1] EXPLICIT C ({ do_XXXXXXXXXXXX_c }),
      			d [2] EXPLICIT B ({ do_XXXXXXXXXXXX_d }),
      			e [3] IMPLICIT C ({ do_XXXXXXXXXXXX_e }),
      			f [4] IMPLICIT INTEGER ({ do_XXXXXXXXXXXX_f })
      			}
      		} ({ do_XXXXXXXXXXXX_A })
      
      	B ::= SET OF OBJECT IDENTIFIER ({ do_XXXXXXXXXXXX_oid })
      
      	C ::= SET OF INTEGER ({ do_XXXXXXXXXXXX_int })
      
      They each have an action (do_XXXXXXXXXXXX_b and do_XXXXXXXXXXXX_e) that
      should only be processed if that element is matched.
      
      The problem is that there's no easy place to hang the action off in the
      subclause (type B for element 'b' and type C for element 'e') because
      subclause opcode sequences can be shared.
      
      To fix this, introduce a conditional action opcode(ASN1_OP_MAYBE_ACT) that
      the decoder only processes if the preceding match was successful.  This can
      be seen in an excerpt from the output of the fixed ASN.1 compiler for the
      above ASN.1 description:
      
      	[  13] =  ASN1_OP_COND_MATCH_JUMP_OR_SKIP,		// e
      	[  14] =  _tagn(CONT, CONS,  3),
      	[  15] =  _jump_target(45),		// --> C
      	[  16] =  ASN1_OP_MAYBE_ACT,
      	[  17] =  _action(ACT_do_XXXXXXXXXXXX_e),
      
      In this, if the op at [13] is matched (ie. element 'e' above) then the
      action at [16] will be performed.  However, if the op at [13] doesn't match
      or is skipped because it is conditional and some previous op matched, then
      the action at [16] will be ignored.
      
      Note that to make this work in the decoder, the ASN1_OP_RETURN op must set
      the flag to indicate that a match happened.  This is necessary because the
      _jump_target() seen above introduces a subclause (in this case an object of
      type 'C') which is likely to alter the flag.  Setting the flag here is okay
      because to process a subclause, a match must have happened and caused a
      jump.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Reviewed-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
      a35dc3f2
    • David Howells's avatar
      ASN.1: Copy string names to tokens in ASN.1 compiler · d8640dbf
      David Howells authored
      Copy string names to tokens in ASN.1 compiler rather than storing a pointer
      into the source text.  This means we don't have to use "%*.*s" all over the
      place.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Reviewed-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
      d8640dbf
  2. 29 Jul, 2015 1 commit
  3. 20 Jul, 2015 24 commits
  4. 19 Jul, 2015 8 commits
  5. 18 Jul, 2015 4 commits
    • Linus Torvalds's avatar
      Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm · 9d37e667
      Linus Torvalds authored
      Pull ARM fixes from Russell King:
       "A small set of ARM fixes for -rc3, most of them not far off
        one-liners, with the exception of fixing the V7 cache invalidation for
        incoming SMP processors which was causing problems for SoCFPGA
        devices"
      
      * 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
        ARM: fix __virt_to_idmap build error on !MMU
        ARM: invalidate L1 before enabling coherency
        ARM: 8404/1: dma-mapping: fix off-by-one error in bitmap size check
        ARM: 8402/1: perf: Don't use of_node after putting it
        ARM: 8400/1: use virt_to_idmap to get phys_reset address
      9d37e667
    • Linus Torvalds's avatar
      Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 0e1dbccd
      Linus Torvalds authored
      Pull x86 fixes from Ingo Molnar:
       "Two families of fixes:
      
         - Fix an FPU context related boot crash on newer x86 hardware with
           larger context sizes than what most people test.  To fix this
           without ugly kludges or extensive reverts we had to touch core task
           allocator, to allow x86 to determine the task size dynamically, at
           boot time.
      
           I've tested it on a number of x86 platforms, and I cross-built it
           to a handful of architectures:
      
                                              (warns)               (warns)
             testing     x86-64:  -git:  pass (    0),  -tip:  pass (    0)
             testing     x86-32:  -git:  pass (    0),  -tip:  pass (    0)
             testing        arm:  -git:  pass ( 1359),  -tip:  pass ( 1359)
             testing       cris:  -git:  pass ( 1031),  -tip:  pass ( 1031)
             testing       m32r:  -git:  pass ( 1135),  -tip:  pass ( 1135)
             testing       m68k:  -git:  pass ( 1471),  -tip:  pass ( 1471)
             testing       mips:  -git:  pass ( 1162),  -tip:  pass ( 1162)
             testing    mn10300:  -git:  pass ( 1058),  -tip:  pass ( 1058)
             testing     parisc:  -git:  pass ( 1846),  -tip:  pass ( 1846)
             testing      sparc:  -git:  pass ( 1185),  -tip:  pass ( 1185)
      
           ... so I hope the cross-arch impact 'none', as intended.
      
           (by Dave Hansen)
      
         - Fix various NMI handling related bugs unearthed by the big asm code
           rewrite and generally make the NMI code more robust and more
           maintainable while at it.  These changes are a bit late in the
           cycle, I hope they are still acceptable.
      
           (by Andy Lutomirski)"
      
      * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86
        x86/fpu, sched: Dynamically allocate 'struct fpu'
        x86/entry/64, x86/nmi/64: Add CONFIG_DEBUG_ENTRY NMI testing code
        x86/nmi/64: Make the "NMI executing" variable more consistent
        x86/nmi/64: Minor asm simplification
        x86/nmi/64: Use DF to avoid userspace RSP confusing nested NMI detection
        x86/nmi/64: Reorder nested NMI checks
        x86/nmi/64: Improve nested NMI comments
        x86/nmi/64: Switch stacks on userspace NMI entry
        x86/nmi/64: Remove asm code that saves CR2
        x86/nmi: Enable nested do_nmi() handling for 64-bit kernels
      0e1dbccd
    • Linus Torvalds's avatar
      Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · dae57fb6
      Linus Torvalds authored
      Pull timer fix from Ingo Molnar:
       "Fix for a misplaced export that can cause build failures in certain
        (rare) Kconfig situations"
      
      * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        tick: Move the export of tick_broadcast_oneshot_control to the proper place
      dae57fb6
    • Linus Torvalds's avatar
      Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · d65b78f5
      Linus Torvalds authored
      Pull scheduler fix from Ingo Molnar:
       "A oneliner rq throttling fix"
      
      * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        sched/fair: Test list head instead of list entry in throttle_cfs_rq()
      d65b78f5